If I wanted to I could run almost 10k miles on oil changes in my 18 year old diesel. At least according to the lab I do 50/50 city highway driving, and use Mobil 1. I don't see a problem with a modern gas engine going 10k-15k, with Mobil 1 of course. If you don't beleive me do what the FSS says and send a sample off to be tested, if it comes back good follow FSS.

Btw Toyota's problem was a design flaw with the crankcase vent. Even cars that had 3k mile changes would sludge up there engines, I think their was a recall.

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2006 CL500
2009 C300 4matic
1969 280SE
2023 Ram 1500
2007 Tiara 3200